As Fleeting as Lightning
by friendlyneighborhoodcanarystan
Summary: Killua was what? B-But last night... KC Undercover/Spy AU


**Alright, so I now have this posted on ao3 as well as here, so lol lemme take my sorry ass to bed!**

Canary reached up, back popping as she stretched. She pursed her lips at the screen filled with her own writing, deciding that here and now would be the stopping point on her essay for the night. She yawned as she sunk down into her bed, about to settle in for the night when her phone vibrated from its place on her nightstand. Canary sighed, contemplating on ignoring the text and checking it in the morning. Sitting up, Canary retrieved the device. It was a message from Killua. Normally Killua would be reason enough to the set the phone aside and turn in for the night but he'd been acting funny around her lately.

She sighed at the mental flash of guilt ridden blue eyes. The body tension, the eye contact avoidance, the overall need to not be around her. She didn't miss any of it. How many times did she need to the pull him aside and reaffirm that she was okay before he stopped beating himself up over something that wasn't his fault?

"Come down. It's important," Canary read under her breath. Oh, so now he wanted to be around her. Good thing her aunt was out getting drinks with Mr. Urahara. She didn't feel like dealing with her teasing.

Canary found Killua sitting on the steps leading up to the front porch when she stepped outside. She watched him rise up.

"Come take a walk with me."

He didn't wait for her to respond, walking down the steps and a bit of a ways down the sidewalk before turning toward her expectantly.

Canary fell into step beside the boy, hoping this walk would result in at least somewhat dispelling the constantly piling tension between them. Their dynamic had shifted in recent times but she'd still try her hand at getting him to stop pulling away from her.

"I don't skip out on a good night's rest for just anyone so you'd better have a good reason for having me out so late," Canary teased.

Killua scoffed, pocketing his hands. "It's not my fault you're a nerd that likes staying up to work on an essay we have due in two months."

Canary blinked. How the hell did he— "Oh, so I should more like you, who puts assignments off until the last minute?"

Killua smirked. "Wait, so I was right? You were _actually_ up this late over that essay? Neeeeerrrd."

Canary stuck her nose up. "Hmph, well, have fun half assin' it at the last minute."

His smirk widened. "Jealous that I pull an A every time with half the effort?"

"Half? More like a fourth!" Canary snorted. Canary turned away to hide the small smile on her face. She'd missed bantering with him like this.

Their walk had taken them to the park. The silence between them was comfortable. The last thing she wanted was to ruin the mood but this had to be said.

"So, does this mean you're done avoiding me?" Canary said bluntly.

Killua came to a stop.

Canary was next to come to a halt, turning back to stare at the quiet spy.

"What do you mean?"

Canary gave him a cross look. "You know _exactly_ what I mean." When it didn't look it he was gonna respond any time soon, Canary continued, "It was out of your control, Killua."

"No, it wasn't."

God, she wished he'd look at her. "What do you mean?"

Killua looked up at her. "It doesn't matter."

Canary sighed in frustration. "Killua—" His lips cut her off.

This couldn't be happening, _shouldn't_ be happening. This was Killua, her best friend's annoying older brother. Things were supposed to never in the course of their relationship escalate this far. When did he… Had he always…

God, and here she was closing her eyes, returning the kiss, enjoying how their lips moved slowly against the other. There was no coming back from this. She still had a chance to put a stop to this by pulling away. But she wasn't. Instead, she was wrapping her hands around his neck and doing nothing to stop him from pulling her closer to him.

He pulled away sooner than she'd like, his lips hovering close enough to where she could easily initiate another kiss. She blinked dazedly. Was this all real? Was she really in Killua's arms, his lips millimeters from her own, his eyes smothering her? She bit her lip, noting the brief jolt of pain. Heh, just her luck. Auntie and Alluka would let her live this down probably around say…never!

She didn't know where to go from here but what she did know was that she needed to sit down for a bit. Pulling away from Killua, Canary approached a nearby bench before sitting down. She didn't look up when Killua sat down next to her. Tonight was definitely a…turn of events. It could've all been avoided if she'd just ignored her phone when she had the chance. Regret was the furthest from what Canary was feeling, though. Her chest felt so light and fluttery.

Canary bit her lip, her hand slowly moving towards Killua's. When hers finally brushed his, she felt Killua jolt, feeling his eyes on her. A warmth encased the entirety of her hand. Canary smiled, glancing over at the pale hand covering her brown one. Canary moved closer before resting her head on Killua's shoulder, closing her eyes. A gentle hand coming around her waist was the last thing she felt before drifting off.

The sound of her phone alarm going off was what brought Canary out of the realm of sleep. Canary sat up, the fog of grogginess slowly dissipating as she realized she was in her bed. She didn't remember settling herself in bed last night… Killua! And the walk! Yes, that's right! They went out on a walk together. And they had… Canary brought a hand up to her lips, fighting off a smile and losing. She and that fool had kissed. Her first kiss and it was given to her by the most annoying person she'd ever met.

A throat being cleared was what made Canary look up. Her aunt stood leant against her doorway, a suspicious smile on her face.

"Mornin', kiddo!"

"Good morning, auntie."

Yoruichi sat down on the edge of her niece's bed, staring out the window. "So, last night Urahara and I came home. I was pretty shitfaced, which is why I thought I was hallucinating when I saw Killua carrying you up to your room."

She had to give herself credit for keeping it cool on the outside because the inside was a different story altogether. Goddammit, she didn't want her aunt to know so soon!

Yoruichi crossed her legs, turning to smirk at her niece. "It turns out it wasn't a hallucination."

Canary remained stoic. "You _were_ hallucinating, auntie."

Yoruichi laughed, shaking her head at the girl. "Why don't you try telling that to the security cameras set up around the house?"

Canary's eyes widened. Fuck, she'd forgotten about those damn things!

Yoruichi grinned. The sweet, sweet taste of victory. How it felt so good early in the morning. "So, tell me, sweet niece of mine. Why was Killua carrying you up to your room?"

The doorbell suddenly rang. Yoruichi scoffed, displeased at the interruption. She got up, pausing near the door to send her niece a smirk over her shoulder. "Don't think we're done, kiddo." The mischievous woman laughed at Canary's groan.

Canary fell back down on the mattress, staring at the ceiling. Would it be awkward when they saw each other next? Would he try to kiss her? Should they tell Alluka now or later? Canary scoffed, turning over on her side. What the hell was she doing!? She was acting like her and Killua were already a thing! It was just one kiss! A kiss…that she certainly wouldn't mind happening again. Over and over.

"Canary."

Canary sat up again, raising an eyebrow at the solemn look on her aunt's face.

"Alluka's here to see you."

Alluka? _Just_ Alluka? Her lips quirked. Killua must've overslept again. He'd be over in a bit. Canary followed her aunt downstairs, unable to shake the strange air about her.

"Good morning, Alluka," Canary greeted as she walked into the living room. When Alluka looked up, teary eyes and a trembling bottom lip was the last thing Canary expected to see. Canary was at her friend's side in no time, wrapping a comforting arm around her. "Alluka, what's wrong?"

Alluka sniffed, tears rolling down her cheeks. "Big Brother's gone."


End file.
